Power tool
AssigneeMakita Corporation
InventorsKiyonobu Yoshikane, Yoshitaka Machida, Kazuki Nakagawa
Life of this patent
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Abstract
A power tool comprises a motor, a final output shaft, a tool body, a detection device, and a braking device. The motor has a motor body including a stator and a rotor, and a motor shaft extending from the rotor and being rotatable around a first rotational axis. The final output shaft is configured to be rotationally driven around a second rotational axis by torque transmitted from the motor shaft. The tool body houses the motor and the final output shaft. The detection device is configured to detect a locking state of the final output shaft. The braking device is configured to directly act on the motor shaft to brake the motor shaft in response to detection of the locking state.
Claims17
A power tool comprising:
- a motor that includes a motor body and a motor shaft, the motor body including a stator and a rotor, the motor shaft extending from the rotor and being rotatable around a first rotational axis;
- a final output shaft that is configured to be rotationally driven around a second rotational axis by torque transmitted from the motor shaft;
- a tool body that houses the motor and the final output shaft;
- a detection device that is configured to detect a locking state of the final output shaft;
- and
- a mechanical braking device that is configured to directly act on the motor shaft to frictionally brake the motor shaft in response to detection of the locking state, wherein:
- the braking device comprises a first rotation member that is fixed to the motor shaft such that the first rotation member rotates integrally with the motor shaft, and
- the braking device further comprises:
- a brake member that is configured to frictionally engage with the first rotation member to brake the motor shaft;
- at least one first biasing member that is configured to bias the brake member away from the first rotation member;
- and
- a pressing member that is (i) a separate member from the brake member, and (ii) configured to press the brake member against the first rotation member, against biasing force of the at least one first biasing member by moving the pressing member toward the brake member, in response to the detection of the locking state.
A power tool comprising:
- a motor that includes a motor body and a motor shaft, the motor body including a stator and a rotor, the motor shaft extending from the rotor and being rotatable around a first rotational axis;
- a final output shaft that is configured to be rotationally driven around a second rotational axis by torque transmitted from the motor shaft;
- a tool body that houses the motor and the final output shaft;
- a detection device that is configured to detect a locking state of the final output shaft;
- and
- a mechanical braking device that is configured to directly act on the motor shaft to frictionally brake the motor shaft in response to detection of the locking state, wherein:
- the braking device comprises a first rotation member that is fixed to the motor shaft such that the first rotation member rotates integrally with the motor shaft, and
- the braking device further comprises:
- a second rotation member that is configured to rotate around the first rotational axis in response to rotation of the motor shaft and the first rotation member while frictionally engaging with the first rotation member,
- at least one biasing member that is configured to bias the second rotation member toward the first rotation member to frictionally engage the second rotation member with the first rotation member, and
- a stopper that is configured to be normally held at a first position where the stopper is incapable of interfering with the second rotation member, and that is configured to move, in response to the detection of the locking state, to a second position where the stopper is capable of interfering with the second rotation member to stop rotation of the second rotation member.
Dependencies are inferred from the claim text.